This application claims priority under 35 U.S.C. § 119(a) on Japanese Patent Application No. 2006-274217, filed Oct. 5, 2006, and on Japanese Patent Application No. 2006-334839, filed Dec. 12, 2006, the contents of which are incorporated herein by reference in their entirety.
The present invention relates to a moving object detection photointerrupter for detecting a moving object, and to an electric device using the same.
Reflective types and transmissive types exist as conventional photointerrupter devices. With the former, or the reflective type, light from a light-emitting element is outputted into the path through which a moving object travels, the light reflected by the moving object is received by a light-receiving element, and the moving object is detected based on a change in the detection output of the light-receiving element at the time of receiving the reflected light. With the latter, or the transmissive type, light outputted from a light-emitting element is received by a light-receiving element via the path of a moving object, and the moving object is detected based on a change in the detection output of the light-receiving element at the time of the light being interrupted by the moving object (refer to JP 2006-71621A and JP2006-136410).
In addition, JP 2006-71621A and JP 2006-136410A disclose a transmissive type device that detects unidirectional movement of a moving object, a medal, or the like. In these devices, plural light receivers are disposed in proximity to one another in the path of the moving object, the medal, or the like. Movement of the moving object, the medal, or the like is detected, and the number of the moving object, the medal, or the like is counted, based on a change in the detection output of each light receiver when the incoming light is interrupted by the moving object, the medal, or the like. Additionally, movement of the moving object, the medal, or the like in the reverse direction is detected as an error.
Furthermore, JP 2001-318164A discloses a transmissive type device that detects movement of an orb. Here, light from light-emitting elements passes into light-receiving elements via the path of the orb. Movement of the orb is detected, and the number of orbs is counted, based on a change in the detection output of each light-receiving element when the incoming light is interrupted by the orb. When only the incoming light of light-receiving elements located downstream in the movement direction is interrupted, the orb is judged to have rebounded, which prevents erroneous detection.
However, with the technology disclosed in JP 2006-71621A and JP 2006-136410A, although movement of the moving object, the medal, or the like in the reverse direction is detected as an error, there are nevertheless mistakes in counting the number of the moving object, the medal, or the like in such cases. For example, when a moving object, a medal, or the like moves and passes in the forward direction, rebounds and passes in the reverse direction, and then once again passes in the forward direction, the same moving object, medal, or the like is counted twice, and thus errors arise in the count value.
Also, with the technology disclosed in JP 2001-318164A, when only the incoming light of light-receiving elements located downstream in the movement direction is interrupted, the orb is judged to have rebounded, and erroneous detection is prevented thereby; however, when the orb once again passes in front of the light-receiving elements in the forward direction after having moved in front of the light-receiving elements in the reverse direction, the same orb is counted twice, and thus errors arise in the count value.